Resize raid array and create second array

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parted /dev/sda
#resize 3
#gave out an error saying unsupported features. It showed what features were supported with resize. I needed to see what features were been used on the partition:
dumpe2fs /dev/sda3
debugfs -w /dev/sda3 -R "features ^ext_attr"
debugfs -w /dev/sda3 -R "features ^resize_inode"
parted was then able to resize the partitions.

mdadm --create /dev/md3 --level 1 --raid-devices=2 /dev/sda3 /dev/sdb3
#I tried to assemble the md2 array using mdadm --assemble /dev/md2 /dev/sda3 /dev/sdb3 but it said that there was no superblock found.
#mdadm examine and detail of md2 and the individual partitions showed no superblock either.
#As a result the array had to be created with the above command. It also resynced itself ok.